Part 2 of the first force problem discussions happened today. The third and final part will happen on Monday.
As always, the second problem was much easier after the first one. As a class, things started coming together even more today. More people spoke who hadn’t talked much in large group discussions yet. They were quicker to call on Talia’s Law (N1L) as part of an argument. Students references things they had tried (with spring scales and masses) in a previous class to convince each other of what must be true. We started getting pickier about things like the relative sizes of forces from one problem to the next and the steepness of the slopes on the velocity-time graphs. In a moment between discussions, one student said, “I feel like I’ve grown so much [as a physics student] today.”
We had a late start to class because of an extended morning meeting for spirit week, otherwise we would have finished the third problem, too. Those boards are ready to go for the start of the next class. They have already started talking about whether there is “left over” force after a push (they’ve decided pretty firmly not). They haven’t yet made a connection between velocity graph steepness and how unbalanced the forces are, so we will see what happens next week.